The mathematical and statistical principles of polyacrylamide gel electrophoresis, SDS polyacrylamide gel electrophoresis, isoelectric focusing, gel filtration and related physical-chemical techniques have been developed. This is to permit optimization of conditions for fractionation of protein and polypeptide hormones, hormone receptors and other macromolecules. Methods have been developed to permit improved statistical estimation of molecular weights derived from these techniques. This project also studies the electrophoresis and sedimentation properties of cells in sucrose gradients and optimization of two-dimensional macromolecular mapping.